Mickelson, winless since the 2013 British Open, lost the clubhead off his 8-iron when it came flying off while he hit from a fairway bunker on the 12th hole.

With gusts reaching 38 mph early in the day, no one with a morning tee time managed to break par. Only Matt Kuchar and Cameron Percy matched it, and conditions might have been worse if not for maintenance crews slithering hoses onto some of the greens to water them down.

The stroke average for the morning wave was 78.61 and the overall average was 75.9.

AP/Darren Abate

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Jimmy Walker

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Jordan Spieth

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Brendan Steele

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Aaron Baddeley

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Billy Horschel

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Phil Mickelson

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Jordan Spieth

Jordan Spieth tees off on the ninth hole during round three of the Valero Texas Open at TPC San Antonio. Spieth finished 1-under on the day for a strong second place 5-under total.

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Zach Johnson

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Chris Kirk

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Chesson Hadley

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Brendan Steele

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Kevin Na

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Jimmy Walker

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Charley Hoffman

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Jimmy Walker, 2015 Valero Texas Open

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Jimmy Walker, 2015 Valero Texas Open

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Jimmy Walker, 2015 Valero Texas Open

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Aaron Baddeley, 2015 Valero Texas Open

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Charley Hoffman, 2015 Valero Texas Open

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Jordan Spieth, 2015 Valero Texas Open

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Kevin Na, 2015 Valero Texas Open

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Phil Mickelson, 2015 Valero Texas Open

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2015 Valero Texas Open

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From the 69 players in the morning, 23 failed to break 80. Jim Furyk and Dustin Johnson managed to keep it in the 70s, but they had their struggles with the wind.

Furyk opened his day with a 52-foot birdie putt, but he shot 76. Johnson had a 78, his worst since shooting a first-round 80 before withdrawing last year from the Houston Open.

U.S. Open champion Martin Kaymer had a two triple bogeys in an 82.

Defending champion Steven Bowditch opened with an 80.

Sam Burns, an 18-year-old high school senior from Sherevport, Louisiana, who earned a spot in the field by winning the Junior PGA Championship last summer, carded an 89 with a quadruple bogey at No. 9.

Hoffman took the lead when he drove near the collar of the 17th green, chipped up and made a 6-footer for birdie.

Graeme McDowell was one of three players from the morning wave who withdrew while shooting high numbers, citing injuries. McDowell, the 2010 U.S. Open champion, said his left ankle and foot were bothering him when he pulled out after a 5-over 41 on his first nine. Sang Moon Bae (back) was 6 over through seven, and Colt Knost (thumb) had it at 9 over through eight with a quadruple bogey at No. 3.